New data supporting that early diagnosis and treatment are possible and necessary in intracellular cobalamin depletion: the case of transcobalamin II deficiency

OBJECTIVES

Transcobalamin II (TC) promotes the cellular uptake of cobalamin (Cbl) through receptor-mediated endocytosis of the TC-cbl complex in peripheral tissues. TC deficiency is a rare disorder that causes intracellular Cbl depletion. It presents in early infancy with a failure to thrive, diarrhea, anemia, agammaglobulinemia, and pancytopenia. Data from five TC-deficient patients including clinical, biochemical, and molecular findings, as well as long-term outcomes, were collected.

CASE PRESENTATION

Mutation analysis revealed one unreported pathogenic variant in the TCN2 gene. One patient had exocrine pancreatic insufficiency. We conducted a retrospective analysis of C3 and C3/C2 from dried blood samples, as this is implemented for newborn screening (NBS). We detected a marked increase in the C3/C2 ratio in two samples. Treatment was based on parenteral Cbl. Three patients treated before six months of age had an initial favorable outcome, whereas the two treated later or inadequately had neurological impairment.

CONCLUSIONS

This is the first report of Argentinean patients with TC deficiency that detected a new variant in TCN2. NBS may be a tool for the early detection of TC deficiency. This data emphasizes that TC deficiency is a severe disorder that requires early detection and long-term, aggressive therapy. Accurate diagnosis is imperative, because early detection and treatment can be life-saving.

[Macrocytic anemia and polychondritis: VEXAS syndrome]

An adult-onset autoinflammatory syndrome caused by somatic mutations in the UBA1 gene on the X chromosome was first reported in 2020. This VEXAS syndrome (acronym for vacuoles, E1 enzyme, X‑linked, autoinflammatory, somatic) is characterized by an overlap of rheumatic inflammatory diseases with separate hematologic abnormalities. A substantial number of affected patients suffer from treatment refractory relapsing polychondritis and nearly always show signs of macrocytic anemia. This case report illustrates the diagnostic key points to recognizing patients with VEXAS syndrome.

Anaemia-based screening for resistance to thyroid hormone alpha in children

BACKGROUND

The hypothyroid phenotype associated with resistance to thyroid hormone alpha (RTH-α) is associated with a diverse clinical picture. On the other hand, thyroid-stimulating hormone (TSH) levels are normal. Free triiodothyronine (fT3) and free thyroxine (fT4) levels can also be normal; however, normo- or macrocytic anaemia is usually present in reported cases. Diagnosis is challenging and there is limited data regarding screening methods.

OBJECTIVE

The study aimed to assess the efficiency of a screening strategy for RTH-α.

SUBJECTS AND METHODS

Out of a total of 6540 children evaluated at the outpatient clinics of paediatric neurology over 2 years and who underwent complete blood count and thyroid function tests, 432 were found to have anaemia. Within this group, we identified 42 children without an underlying specific neurological aetiology who exhibited normo- or macrocytic anaemia, normal TSH levels, fT3 levels in the upper half of the normal range or high, and fT4 levels in the lower half of the normal range or low. We excluded one patient who had already been diagnosed with RTH-α and nine patients could not be reached. Subsequently, clinical evaluation, biochemical assessment, and THRA sequencing analysis were conducted on 32 children. The findings were compared with those of the known RTH-α patients in our unit.

RESULTS

The median age of the patients was 5.7 (5.1-7.4) years, and 22 of them were males (69%). The main reasons for assessment in paediatric neurology clinics were autism spectrum disorder (n = 12, 38%), epilepsy (n = 11, 34%), and delay in developmental stages (n = 8, 25%). Constipation was present in five of the cases (16%), while the closure of the anterior fontanelle and tooth eruption were delayed in two cases (6%) and one case (3%), respectively. The median length/height and weight standard deviation (SD) scores were 0.3 [(-0.8)-(1.1)] and -0.1 [(-0.8)-(0.3)], respectively. The median fT3, fT4, and TSH levels were 4.6 (4.2-5.0) pg/mL, 0.9 (0.8-1.0) ng/dL, and 2.2 (1.8-3.1) uIU/mL, respectively. Thirteen of the patients (41%) had high fT3 levels, while none of them had low fT4 levels. The normo- or macrocytic anaemia rate was 47% (normocytic/macrocytic, n = 8/7) at the time of reassessment. Serum creatine kinase (CK) was elevated in five patients (16%; one had anaemia). None of the subjects had a pathological variant in THRA. Known RTH-α patients had significantly lower median height SD score, higher rates of delayed tooth eruption and closure of the anterior fontanelle, lower haemoglobin levels, and higher mean corpuscular volume (MCV) and CK levels as compared to those found without RTH-α.

CONCLUSIONS

This approach found one known patient with RTH-α but did not reveal any new cases. Notably, normo- or macrocytic anaemia did not persist in nearly half of the screened patients. A screening strategy that takes clinical findings and prominent laboratory features suggestive of RTH-α into account could lower unnecessary genetic analysis of THRA in patients presenting with neurological problems.

Biallelic hypomorphic variants in CAD cause uridine-responsive macrocytic anaemia with elevated haemoglobin-A2

Biallelic pathogenic variants in CAD, that encode the multienzymatic protein required for de-novo pyrimidine biosynthesis, cause early infantile epileptic encephalopathy-50. This rare disease, characterized by developmental delay, intractable seizures and anaemia, is amenable to treatment with uridine. We present a patient with macrocytic anaemia, elevated haemoglobin-A2 levels, anisocytosis, poikilocytosis and target cells in the blood smear, and mild developmental delay. A next-generation sequencing panel revealed biallelic variants in CAD. Functional studies did not support complete abrogation of protein function; however, the patient responded to uridine supplement. We conclude that biallelic hypomorphic CAD variants may cause a primarily haematological phenotype.

Mean corpuscular volume as a prognostic factor for 30-day mortality in major trauma patients: a retrospective cohort study

We investigated the clinical implications of the mean corpuscular volume (MCV) in patients with major trauma. This single-center retrospective review included 2021 trauma patients admitted to the intensive care unit between January 2016 and June 2020. We included 1218 patients aged [Formula: see text] 18 years with an injury severity score [Formula: see text] 16 in the final analysis. The clinical and laboratory variables were compared between macrocytosis (defined as MCV [Formula: see text] 100 fL) and non-macrocytosis groups. Cox regression analysis was performed to calculate the hazard ratios (HRs) of variables for 30-day mortality, with adjustment for other potential confounding factors. The initial mean value of MCV was 102.7 fL in the macrocytosis group (n = 199) and 93.7 fL in the non-macrocytosis group (n = 1019). The macrocytosis group showed a significantly higher proportion of initial hypotension, transfusion within 4 and 24 h, and 30-day mortality than the non-macrocytosis group. Age ([Formula: see text] 65 years), hypotension (systolic blood pressure [Formula: see text] 90 mmHg), transfusion (within 4 h), anemia (Hb < 12 g/day in women, < 13 g/day in men), and macrocytosis were significantly associated with 30-day mortality (adjusted HR = 1.4; 95% confidence interval 1.01-1.94; p = 0.046) in major trauma patients. Thus, initial macrocytosis independently predicted 30-day mortality in patients with major trauma at a Level I trauma center.

Macrocytic anemia induced by selenium deficiency in the course of anorexia nervosa: A case report

RATIONALE

Anorexia nervosa is characterized by an extreme fear of weight gain. Clinicians often prescribe meal replacement shakes if patients are unable or unwilling to consume typical foods. However, these shakes sometimes lack essential micronutrients, such as selenium, which may lead to health risks. Moreover, selenium deficiency induces macrocytic anemia. Herein, we present a case of a patient with anorexia nervosa with macrocytic anemia due to selenium deficiency, which was alleviated by selenium supplementation.

PATIENT CONCERNS

An 18-year-old female was admitted to our hospital. The patient was diagnosed with anorexia nervosa. Ultimately, she was unable to walk independently because of fatigue and electrolyte disturbances.

CLINICAL FINDINGS

On admission, the height, weight, and body mass index of the patient were 158.5 cm, 27.1 kg, and 10.8, respectively. Our treatment for anorexia nervosa showed relative effectiveness, and the patient's body weight recovered to 29.2 kg by day 60. However, the mean corpuscular volume increased from day 20, suggesting macrocytic anemia.

DIAGNOSES, INTERVENTIONS, AND OUTCOMES

Despite our vitamin B12 and folic acid supplementation interventions, the mean corpuscular volume continued to rise. On day 60, the patient was diagnosed with selenium deficiency, and selenium administration of 100 μg/day was initiated.

OUTCOMES

The macrocytic anemia in the patient was alleviated, and treatment for anorexia nervosa was continued in our hospital.

LESSONS

To the best of our knowledge, this is the first case of macrocytic anemia induced by selenium deficiency with anorexia nervosa comorbidity, underscoring the importance of selenium supplementation in patients with anorexia nervosa, especially in those with macrocytic anemia.

Case report: Severe combined immunodeficiency with ligase 1 deficiency and Omenn-like manifestation

DNA ligase I deficiency is an extremely rare primary immunodeficiency with only 6 patients reported in the literature. Most common manifestations include radiosensitivity, macrocytic anemia, lymphopenia with an increased percentage of gamma-delta T cells, and hypogammaglobulinemia requiring replacement therapy. Two-month-old girl with delayed development, T-B-NK+ SCID, and macrocytic anemia presented features of Omenn syndrome. Whole exome sequencing revealed two novel, heterozygous variants (c.2312 G>A, p.Arg771Gly and c.776+5G>T, p.Pro260*) in the LIG1 gene (NM_000234.1). Hematopoietic stem cell transplantation from a fully matched unrelated donor was performed at the age of 4 months using GEFA03 protocol. Mixed donor-recipient chimerism was observed, with 60-70% chimerism in the mononucleated cell compartment and over 90% in T-lymphocyte compartment, but autologous myeloid recovery. Stable CD4+ and CD8+ T-cell counts above 200/µL were achieved after 2 months, but the patient remained transfusion-dependent. Despite satisfactory immunological reconstitution, the second transplantation due to constitutional hemolytic defect has been considered. In light of possible re-transplantation, an issue of optimal conditioning protocol with sufficient myeloid engraftment is important. For the first time Omenn syndrome is described in a compound heterozygote carrying two the novel variants p.Arg771Gly and p.Pro260* in the LIG1 gene. Patients diagnosed with SCID and Omenn syndrome showing macrocytic anemia, should be screened for DNA ligase I deficiency.

Centrosome function is critical during terminal erythroid differentiation

Red blood cells are produced by terminal erythroid differentiation, which involves the dramatic morphological transformation of erythroblasts into enucleated reticulocytes. Microtubules are important for enucleation, but it is not known if the centrosome, a key microtubule-organizing center, is required as well. Mice lacking the conserved centrosome component, CDK5RAP2, are likely to have defective erythroid differentiation because they develop macrocytic anemia. Here, we show that fetal liver-derived, CDK5RAP2-deficient erythroid progenitors generate fewer and larger reticulocytes, hence recapitulating features of macrocytic anemia. In erythroblasts, but not in embryonic fibroblasts, loss of CDK5RAP2 or pharmacological depletion of centrosomes leads to highly aberrant spindle morphologies. Consistent with such cells exiting mitosis without chromosome segregation, tetraploidy is frequent in late-stage erythroblasts, thereby giving rise to fewer but larger reticulocytes than normal. Our results define a critical role for CDK5RAP2 and centrosomes in spindle formation specifically during blood production. We propose that disruption of centrosome and spindle function could contribute to the emergence of macrocytic anemias, for instance, due to nutritional deficiency or exposure to chemotherapy.

Human radical scavenger α1-microglobulin protects against hemolysis in vitro and α1-microglobulin knockout mice exhibit a macrocytic anemia phenotype

During red blood cell (RBC) lysis hemoglobin and heme leak out of the cells and cause damage to the endothelium and nearby tissue. Protective mechanisms exist; however, these systems are not sufficient in diseases with increased extravascular hemolysis e.g. hemolytic anemia. α₁-microglobulin (A1M) is a ubiquitous reductase and radical- and heme-binding protein with antioxidation properties. Although present in the circulation in micromolar concentrations, its function in blood is unclear. Here, we show that A1M provides RBC stability. A1M^-/- mice display abnormal RBC morphology, reminiscent of macrocytic anemia conditions, i.e. fewer, larger and more heterogeneous cells. Recombinant human A1M (rA1M) reduced in vitro hemolysis of murine RBC against spontaneous, osmotic and heme-induced stress. Moreover, A1M is taken up by human RBCs both in vitro and in vivo. Similarly, rA1M also protected human RBCs against in vitro spontaneous, osmotic, heme- and radical-induced hemolysis as shown by significantly reduced leakage of hemoglobin and LDH. Addition of rA1M resulted in decreased hemolysis compared to addition of the heme-binding protein hemopexin and the radical-scavenging and reducing agents ascorbic acid and Trolox (vitamin E). Furthermore, rA1M significantly reduced spontaneous and heme-induced fetal RBC cell death. Addition of A1M to human whole blood resulted in a significant reduction of hemolysis, whereas removal of A1M from whole blood resulted in increased hemolysis. We conclude that A1M has a protective function in reducing hemolysis which is neither specific to the origin of hemolytic insult, nor species specific.

How Altered Ribosome Production Can Cause or Contribute to Human Disease: The Spectrum of Ribosomopathies

A number of different defects in the process of ribosome production can lead to a diversified spectrum of disorders that are collectively identified as ribosomopathies. The specific factors involved may either play a role only in ribosome biogenesis or have additional extra-ribosomal functions, making it difficult to ascribe the pathogenesis of the disease specifically to an altered ribosome biogenesis, even if the latter is clearly affected. We reviewed the available literature in the field from this point of view with the aim of distinguishing, among ribosomopathies, the ones due to specific alterations in the process of ribosome production from those characterized by a multifactorial pathogenesis.

Pernicious anemia in a young man with systemic lupus erythematosus

Association of pernicious anemia and systemic lupus erythematosus is rare, although both diseases are autoimmune origin. We describe the case of a 40-year old man with systemic lupus erythematosus (SLE) who developed pernicious anemia. The cobalamin deficiency was revealed by macrocytic pancytopenia. After 1 month of vitamin B12 treatment, hemoglobin and white blood cell count remain normal but thrombocytopenia persists and was considered as immunologic from SLE origin requiring corticosteroids. Lupus (2007) 16, 827—829.

[Serum Erythropoietin as Prognostic Marker in Myelodysplastic Syndromes]

INTRODUCTION

This myelodysplastic syndromes are a heterogeneous entity characterized by dysplasia, hypercellular bone marrow, cytopenias and risk of transformation to acute leukaemia. Prognostic factors, such as bone marrow fibrosis, lactate dehydrogenase and 2-microglobulin elevation have been described, but treatment is mainly based in the International Prognostic Scoring System.

MATERIAL AND METHODS

Our aim was to analyze serum's erythropoietin at diagnosis in de novo myelodysplastic syndromes patients, through its impact in overall survival and possible implementation as prognostic marker. Clinical and laboratorial data from 102 patients with de novo myelodysplastic syndromes diagnosed between October/2009 and March/2014 were collected. Survival analysis was performed according to serum erythropoietin level stratification, using Kaplan-Meier methodology.

RESULTS

Our 102 patients had a median age of 74 years, with a male:female ratio of 0.8. Mean erythropoietin was significantly lower in refractory cytopenia with unilineage dysplasia patients in contrast with the higher values observed in 5q- syndrome (p < 0.05). Eleven patients progressed to acute leukaemia; these have higher mean erythropoietin values (p < 0.05). In addition, elevated serum erythropoietin was associated with lower survival rates (p = 0.0336). Predictive value of serum erythropoietin was maintained after Cox regression adjustment. In multivariate analysis, serum erythropoietin is an independent survival predictor (p < 0.001).

DISCUSSION

Serum erythropoietin is a predictive factor for response to therapy with subcutaneous erythropoietin, and patients with myelodysplastic syndromes with higher values of erythropoietin have poorer response to administration of erythropoietin even at higher doses. Our sample shows that serum erythropoietin also has prognostic value, and in all myelodysplastic syndromes subtypes. Moreover, alone or in combination with other factors or prognostic indices, erythropoietin may enhance the prognostic indices such as the International Prognostic Scoring System, since high levels are associated with progression to acute leukemia and hence lower survival.

CONCLUSION

This study suggests that increased erythropoietin levels at diagnosis can by itself be a poor prognosis factor inmyelodysplastic syndromes patients, with higher values in patients with progression to acute leukaemia and decreased overall survival.

[Effective azacitidine treatment for myelodysplastic syndrome transformed from essential thrombocythemia]

A 68-year-old woman with essential thrombocythemia had been treated with hydroxycarbamide and aspirin for 13 years. She exhibited the rapid progression of anemia, and a bone marrow examination showed dysplasia of the erythroid cells, myeloid cells, and megakaryocytes. Karyotype analysis indicated complex abnormalities including der (5;21)(p10;q10). She was diagnosed with myelodysplastic syndrome (MDS), refractory anemia with excess blasts-1 (RAEB-1). Lenalidomide was started, but no improvement in anemia was recorded. Lenalidomide was discontinued due to eosinophilia, basophilia, and a skin rash. Azacitidine was administered. The patient became transfusion independent, and a complete cytogenetic response was achieved with three courses of azacitidine. However, disease progression to acute myeloid leukemia (AML) was observed after an additional two courses of azacitidine, which was resistant to induction chemotherapy. The patient died five months later from AML transformation. Azacitidine may be effective in MDS transformed from essential thrombocythemia, and also in lenalidomide-resistant MDS with the deletion of 5q.

Multiple carcinoids in the duodenum, pancreas and stomach accompanied with type A gastritis: A case report

We report a case of multiple duodenal, pancreatic, and gastric carcinoids. A 67-year old woman was admitted to our hospital for treatment of a duodenal carcinoid. Laboratory tests revealed that the patient was associated with macrocytic anemia and hypergastrinemia, and type A gastritis was shown by gastrofiberscopy. During surgery, another tumor was incidentally found in the head of the pancreas. The tumors in the duodenum and pancreas were completely excised by pancreatoduodenectomy and immunohistologically diagnosed as gastrin-and serotonin-producing carcinoids, respectively. Pathological examination revealed that in addition to the grossly found carcinoids, there were subclinical carcinoids, one of which was an endocrine cell micronest, located in the stomach and duodenum. The tumors in the duodenum, pancreas, and stomach showed different characteristics from one another morphologically and immunochemically. Although no definitive evidence has been obtained, some sort of genetic anomaly may have been involved in this case, and hypergastrinemia due to duodenal gastrinoma may induce multiple gastric carcinoids.

[Developing undergraduate medical boarding's clinical aptitude in anemic deficiencies with a participation promotive educational strategy]

OBJECTIVE

To compare the profit of a participation promotive educational strategy versus traditional teaching on development of the undergraduate medical boarding's clinical aptitude.

METHODS

A quasiexperimental design was made. An instrument was built and validated in order to explore clinical aptitude. It contains three actual clinical cases about iron, folic acid or cobalamin deficiency, and a questionnaire with 164 items to explore eight clinical aptitude indicators; experts attending and teaching physicians validated it. A Kuder-Richardson coefficient of 0.80 was gotten when we estimated the internal reliability. The instrument was applied simultaneously to 55 undergraduate medical boarding from two hospitals of the Instituto Mexicano del Seguro Social the starting year of undergraduate boarding (initial measuring) and at finish once again (end measuring). The experimental group (GE, n = 29) was exposed to a participation promotive educational strategy, and control group (GC, n = 26) to a traditional one.

RESULTS

The overall scores of initial measuring in the GE and GC were low: 57 y 42 respectively (maximum: 164); at end measuring an increase in overall scores was observed: in the GE 68 (p < 0.02) and GC 47 (NS).

CONCLUSIONS

The participation promotive educational strategy is better than traditional teaching for developing the undergraduate medical boarding's clinical aptitude. It must be considerated to propitiate changes to develop a more reflexive and critical education.

Congenital dyserythropoietic anemia type I (CDA I): molecular genetics, clinical appearance, and prognosis based on long-term observation

Congenital dyserythropoietic anemia type I (CDA I) is a rare autosomal recessive disorder with ineffective erythropoiesis and iron overloading. More than 100 cases have been described, but with the exception of a report on a large Bedouin tribe, these reports include only small numbers of cases, and no data on the lifetime evolution of the disease are available. Since 1967, we have been able to follow 21 cases from 19 families for up to 37 years. Twenty-one patients with a confirmed diagnosis of CDA I exhibited chronic macrocytic anemia of variable severity, requiring regular red cell transfusions only in 2 individuals. Four developed gallstones before the age of 30 years. Fifteen of 16 cases alive at the time of analysis showed mutations of at least one allele from exons 6 to 28 within CDAN1. Iron overloading is to be expected in all patients. In 9 patients, iron depletion was started between the ages of 7 and 36 years. Splenectomy, which was performed in 7 patients, did not result in improvement of hemoglobin values. Five patients were treated with interferon alpha-2a, and all responded with a rise in hemoglobin concentration of between 25 and 35 g/L (2.5 and 3.5 g/dL) starting within 4 weeks.

Remission of transfusion-dependent myelodysplastic syndrome in association with respiratory tract infection

We describe a case of blood transfusion-dependent myelodysplastic syndrome (refractory anaemia), associated with macrocytosis and elevated percentage of hypochromic cells. Following an acute hospital admission with a respiratory tract infection, the patient entered a complete and sustained remission.